Self-sustaining cracking of hydrocarbons

Abstract

The present disclosure provides a simple and efficient method for the self-sustaining radiation cracking of hydrocarbons. The method disclosed provides for the deep destructive processing of hydrocarbon chains utilizing hydrocarbon chain decomposition utilizing self-sustaining radiation cracking of hydrocarbon chains under a wide variety of irradiation conditions and temperature ranges (from room temperature to 400° C.). Several embodiments of such method are disclosed herein, including; (i) a special case of radiation-thermal cracking referred to as high-temperature radiation cracking (HTRC); (ii) low temperature radiation cracking (LTRC); and (iii) cold radiation cracking (CRC). Such methods were not heretofore appreciated in the art. In one embodiment, a petroleum feedstock is subjected to irradiation to initiate and/or at least partially propagate a chain reaction between components of the petroleum feedstock. In one embodiment, the treatment results in hydrocarbon chain decomposition; however, other chemical reactions as described herein may also occur.

1. A method of treating a petroleum feedstock by initiating a high-rate, self-sustaining chain cracking reaction in the petroleum feedstock to generate a treated petroleum feedstock, said method comprising subjecting the petroleum feedstock to ionizing irradiation, wherein the petroleum feedstock is subjected to a time-averaged irradiation dose rate of at least about 5.0 kGy/s and a total absorbed irradiation dose of at least about 0.1 kGy, and wherein the temperature of the petroleum feedstock during irradiation treatment is less than about 200° C, said irradiation treatment resulting in an increase in the radiation-chemical yield of light fractions boiling out below 450° C. and a decrease in heavy residue boiling out above 450° C. 
     
     
       2. The method of  claim 1 , wherein the petroleum feedstock is flowing during irradiation. 
     
     
       3. The method of  claim 2 , where the time-averaged irradiation dose rate is about 10 kGy/s or greater, the total absorbed irradiation dose is from about 1.0 to about 5.0kGy. 
     
     
       4. The method of  claim 2 , where the time-averaged irradiation dose rate is about 15 kGy/s or greater, the total absorbed irradiation dose is from about 1.0 to about 10.0kGy. 
     
     
       5. The method of  claim 2 , wherein the depth of the flowing petroleum feedstock during irradiation is between about 0.5 mm and 10 cm. 
     
     
       6. The method of  claim 1 , wherein the time-averaged irradiation dose rate is at least about 15 kGy/s. 
     
     
       7. The method of  claim 1 , wherein the temperature of the petroleum feedstock during irradiation is less than about 100° C. 
     
     
       8. The method of  claim 1 , wherein said ionizing irradiation is provided by electrons. 
     
     
       9. The method of  claim 8 , wherein said electrons have an energy of from about 1 to about 10 MeV. 
     
     
       10. The method of  claim 9 , wherein the irradiation treatment provides a radiation-chemical yield of light fractions of at least about 10 molecules/100 eV. 
     
     
       11. The method of  claim 9 , wherein the irradiation treatment provides a radiation-chemical yield of light fractions of at least about 100 molecules/100 eV. 
     
     
       12. The method of  claim 1 , wherein the pressure during irradiation treatment is in the range of atmospheric pressure to about 3 atmospheres. 
     
     
       13. The method of  claim 1 , further comprising thermal, mechanical, acoustic, or electromagnetic treatment of the petroleum feedstock prior to irradiation treatment, during irradiation treatment, or both prior to and during irradiation treatment. 
     
     
       14. The method of  claim 1 , further comprising treatment of the petroleum feedstock with an agent prior to or during irradiation treatment, the agent being selected from the group consisting of ionized air, water, steam, ozone, oxygen, hydrogen, methanol, and methane. 
     
     
       15. The method of  claim 1 , further comprising bubbling water vapor or ionized air through the petroleum feedstock prior to or during irradiation treatment. 
     
     
       16. The method of  claim 1 , wherein said subjecting step comprises injecting the petroleum feedstock into a reaction vessel in a dispersed form. 
     
     
       17. The method of  claim 1 , wherein the petroleum feedstock is selected from the group consisting of crude oil, high-viscous heavy crude oil, high-paraffin crude oil, fuel oil, tar, heavy residua of oil processing, wastes of oil extraction, bitumen, and used oil products. 
     
     
       18. The method of  claim 1 , wherein the total absorbed dose is less than a limiting dose of irradiation as defined by the stability of the treated petroleum feedstock, the limiting dose of irradiation and a reaction rate of the treated petroleum feedstock being regulated by a variation in the time-averaged dose rate, a flow condition parameter, an optional structural or chemical modification of the petroleum feedstock, or a combination of the foregoing. 
     
     
       19. The method of  claim 18 , wherein the stability of the treated petroleum feedstock is determined by reference to post-treatment changes in the concentration of light fractions within the treated petroleum feedstock.